function load(box, url){
    return new Promise((resolve,reject)=>{
        let xhr = new XMLHttpRequest();
        xhr.open("get",url);
        xhr.send();
        xhr.onload = function(){
            if(xhr.status === 200){
                box.innerHTML = xhr.responseText
                resolve(xhr.responseText)
            }else{
                reject(xhr.status)
            }
        }
    })
}